docs: Add simple file transfer example

Cargo.toml

@@ -95,7 +95,7 @@ futures-util = "0.3.30"
 testdir = "0.9.1"
 
 [features]
-default = ["fs-store", "rpc", "net_protocol", "example-iroh"]
+default = ["fs-store", "rpc", "net_protocol"]
 downloader = ["dep:parking_lot", "tokio-util/time", "dep:hashlink"]
 net_protocol = ["downloader"]
 fs-store = ["dep:reflink-copy", "redb", "dep:redb_v1", "dep:tempfile"]
@@ -134,6 +134,9 @@ name = "fetch-fsm"
 [[example]]
 name = "fetch-stream"
 
+[[example]]
+name = "transfer"
+
 [[example]]
 name = "hello-world-fetch"
 required-features = ["example-iroh"]

examples/transfer.rs

@@ -0,0 +1,100 @@
+use std::{path::PathBuf, str::FromStr};
+
+use anyhow::Result;
+use iroh::{protocol::Router, Endpoint};
+use iroh_base::ticket::BlobTicket;
+use iroh_blobs::{
+    net_protocol::Blobs,
+    rpc::client::blobs::{ReadAtLen, WrapOption},
+    store::mem,
+    util::{local_pool::LocalPool, SetTagOption},
+};
+
+#[tokio::main]
+async fn main() -> Result<()> {
+    // Create an endpoint, it allows creating and accepting
+    // connections in the iroh p2p world
+    let endpoint = Endpoint::builder().discovery_n0().bind().await?;
+
+    // We initialize the Blobs protocol in-memory
+    let local_pool = LocalPool::default();
+    let blobs = Blobs::memory().build(&local_pool, &endpoint);
+
+    // Now we build a router that accepts blobs connections & routes them
+    // to the blobs protocol.
+    let node = Router::builder(endpoint)
+        .accept(iroh_blobs::ALPN, blobs)
+        .spawn()
+        .await?;
+
+    let args = std::env::args().collect::<Vec<_>>();
+    match &args.iter().map(String::as_str).collect::<Vec<_>>()[..] {
+        [_cmd, "send", path] => {
+            let abs_path = PathBuf::from_str(path)?.canonicalize()?;
+
+            let blobs = node
+                .get_protocol::<Blobs<mem::Store>>(iroh_blobs::ALPN)
+                .unwrap()
+                .client();
+
+            println!("Analyzing file.");
+
+            let blob = blobs
+                .add_from_path(abs_path, true, SetTagOption::Auto, WrapOption::NoWrap)
+                .await?
+                .finish()
+                .await?;
+
+            let node_id = node.endpoint().node_id();
+            let ticket = BlobTicket::new(node_id.into(), blob.hash, blob.format)?;
+
+            println!("File analyzed. Fetch this file by running:");
+            println!("cargo run --example transfer -- receive {ticket} {path}");
+
+            tokio::signal::ctrl_c().await?;
+        }
+        [_cmd, "receive", ticket, path] => {
+            let path_buf = PathBuf::from_str(path)?;
+            let ticket = BlobTicket::from_str(ticket)?;
+
+            let blobs = node
+                .get_protocol::<Blobs<mem::Store>>(iroh_blobs::ALPN)
+                .unwrap()
+                .client();
+
+            println!("Starting download.");
+
+            blobs
+                .download(ticket.hash(), ticket.node_addr().clone())
+                .await?
+                .finish()
+                .await?;
+
+            println!("Finished download.");
+            println!("Copying to destination.");
+
+            let mut file = tokio::fs::File::create(path_buf).await?;
+            let mut reader = blobs.read_at(ticket.hash(), 0, ReadAtLen::All).await?;
+            tokio::io::copy(&mut reader, &mut file).await?;
+
+            println!("Finished copying.");
+        }
+        _ => {
+            println!("Couldn't parse command line arguments.");
+            println!("Usage:");
+            println!("    # to send:");
+            println!("    cargo run --example transfer -- send [FILE]");
+            println!("    # this will print a ticket.");
+            println!();
+            println!("    # to receive:");
+            println!("    cargo run --example transfer -- receive [TICKET] [FILE]");
+        }
+    }
+
+    // Gracefully shut down the node
+    println!("Shutting down.");
+    node.shutdown().await?;
+    local_pool.shutdown().await;
+
+    Ok(())
+}